1. Field of the Invention
This invention relates to a clamping device for fixing a disklike rotary cutter to a rotatable toolholder, which is adapted to be driven, specifically to such a device for clamping a rotary cutter having a planar contact surface which is associated with a planar end face of the toolholder, wherein the rotary cutter is adapted to be clamped against the toolholder by means of axially acting load-applying means and clamping means which are formed with a conical seating surface for engaging the rotary cutter and with a cylindrical seating surface for engaging the toolholder with elastic deformation.
2. Description of the Prior Art
Rotary cutters of machine tools, such has externally or internally cutting milling wheels or grinding disks, cannot machine a workpiece with the required precision unless they are radially and axially aligned with respect to the toolholder, which may consist of a driving spindle or a toolholding drum. For that reason the means for clamping the rotary cutter are required also to determining a proper position for the rotary cutter. From U.S. Pat. No. 1,472,565 and EP-A No. 1 0 208 786 it is already known that an axial and radial alignment of the cutter can be ensured in that the rotary cutter is not fixed directly to the toolholder but is indirectly fixed thereto by means of separate clamping elements, which permit an adjustment of the rotary cutter in radial and axial directions without a backlash. Because the clamping elements have a cylindrical seating surface, they can axially be adjusted relative to the toolholder so that the axial clamping by the axial component of force which is due to the conical seating surface causes the contacting surface of the rotary cutter to bear on the associated end face of the toolholder and to be exactly axially aligned. After that axial alignment the axial clamping which is effected by the radial component of force that is due to the conical seating interface ensures that the rotary cutter will properly be centered and, owing to the contact between the contacting surface of the rotary cutter and the end face of the toolholder, the clamping element will be subjected to an elastic deformation at the cylindrical seating interface so that there is no backlash at the cylindrical seating interface between the clamping element and the toolholder and the rotary cutter is exactly radially aligned. The purely axial clamping action of the clamping element and the fact that it is capable of elastic deformation - this can be ensured by a proper selection of the material and/or design of the clamping element - will ensure that the rotary cutter can be adjusted and fixed with very high accuracy. But in the previous practice it is necessary to remove all clamping elements and load-applying members when the rotary cutters are to be removed from and mounted on the toolholder so that a change of the rotary cutter will involve rather difficult and time-consuming work. Besides, the known clamping device can be used only with toolholding spindles.